pub fn convert_base(num_str: &str, to_base: u32) -> String {
    // 解析输入字符串中的数字和其基数
    let parts: Vec<&str> = num_str.split('(').collect();
    let number_str = parts[0]; // 原始数字字符串
    let from_base: u32 = parts[1].trim_end_matches(')').parse().unwrap(); // 原始数字的基数

    // 将原始数字字符串转换为十进制整数
    let number = isize::from_str_radix(number_str, from_base as u32).unwrap();

    // 将十进制整数转换为目标基数的字符串
    let mut result = String::new();
    let digits = "0123456789abcdefghijklmnopqrstuvwxyz";
    let mut n = number;

    while n > 0 {
        let index = (n % to_base as isize) as usize;
        if let Some(digit) = digits.chars().nth(index) {
            result.insert(0, digit);
        }
        n /= to_base as isize;
    }

    if result.is_empty() {
        result.push('0');
    }

    result
}